Siphonage preventer for plumbing systems



May 23, 1939. R R, ox

SIPHONAGE 'PREVE'NTER FOR PLUMBING SYSTEMS Filed Sept. .22, 1937 2 Sheets-Shee't l in van ion Roberi R Fan.

' May 23, 1939. R. R. FOX

SIPHONAGE PREVENTER FOR PLUMBING SYSTEMS Filed Sept 22, 1937 2 Sheets-Sheet 2 In venio n I Robert 12. Pope.

Patented May 23, 1939 UNITED STATES 10 Claims.

This invention relates generally to devices for supply lines. The invention is applicable to water supply line outlets generally, though a particular application consists in its installation in connection with flush valves, and the invention will accordingly be herein described with that particular situation chiefly in view, but without necessary limitation thereto.

It is a well known fact that under certain conditions, water may be sucked backwardly through a water outlet into the water supply lines. This may be due to exhaustion of water in the mains, or to reduction of pressure in the main or in the 5 line that supplies the outlet. Assuming the outlet to be connected to a flush valve installed in connection with a toilet bowl, the flush valve normally being held closed by the pressure in the water line, it will be seen that reduction of pressure in the mains may cause an actual suction in the water supply line, and this may cause the flush valve to open, allowing the suction to continue on down into the bowl, and in some intion is to provide a siphonage preventer which is not only simple, but rugged and dependable in service, and one which is not liable to become disordered by reason of corrosion.

The particular characteristics of the present invention will best be understood by now referring at once to the following detailed description of ,a present preferred embodiment thereof, reference for this purpose being had to the accompanying drawings, in which: Fig. l is a side elevation of the device in accordance with the present invention;

Fig. 2 is atop plan view of the device;

Fig. 3 is a vertical medial section taken on line 33 of Fig. 2; l Fig. 4 is a vertical cross section taken at right angles to Fig. 3, as indicated by lines 4-.4 of Fig. 2;

Fig. 5 is an end elevation of the device;

Fig. 6 is a view looking upwardly into the upper member of the device;

preventing back-siphonage of water into water stances may lift the water out of the bowl into i-ATENT OFFICE Robert R. Fox, Los Angeles, (lalil'.

Application September 22, 1937, Serial No. 165,140

Fig. '7 is a view looking downwardly into the lower member of the device; and

Fig. 8 is a fragmentary view similar to a portion of Fig. 4, showing a modification.

As mentioned above, a siphonage preventing '5 device of the instant type may be associated with or incorporated in any conduit wherein liquid normally flows in one direction but wherein reversal of flow due to a vacuum developed ahead of the device would be objectionable. ,A device 10 of this type is, for instance, adapted to be used with a flush valve, such for example as of the valve disclosed in United States Patent No. 2,066,086 to E. C. Wilson, being installed in the flow line between the flush valve outlet and the lli bowl served by the valve.

In the present illustrative embodiment of the invention, the siphonage preventer embodies a hollow body B formed with certain liquid'and air passageways, in the present illustrative embodi- 20 ment comprising an upper member [0, provided at the top with an internally screw-threaded in-' let I l adapted to be coupled to the discharge outlet of a flush valve, or water supply line, and a lower member If! screw-threadedly connected to 5 member ID and provided at the bottom with an externally screw-threaded outlet I4 adapted for screw-threaded connection with the flow line leading to the bowl, or other container supplied by the liquid line. 30

Top member Ill may be described as generally bell shaped in external form. A hollow bridgelike member it extends transversely across the interior of the "bell, and has, concentric with inlet I I, a depending externally threaded annular 35 flange H. A liquid passage or conduit 20 ex.- tends downwardly from inlet H to the upper surface of member It, then divides into two branches extending outwardly and downwardly around the sides of member [6 to open to later 40 described passageways in lower member l2- Member ID has at the bottom a circular downwardly facing, recessed seat 22, and has alined with hollow member l6, diametrically opposed overhanging extensions 23 outside said seat, through which extend passages 24 leading from the hollow interior I612 of member l6, said passages curving downwardly to open in a downward direction, under the bell, as clearly illus 0 trated in Fig. 3. Passages 24 communicate by way of hollow I61) with a circular opening or air port 25 in the lower wall 26 of hollow member l6, and the lower surface of said wall 26, inside flange l1, and around port 25, affords a downwardly 55 facing valve seat 21 for a check valve 28, later to be described in more detail.

Passages 24 afford pathways for the admission of air downwardly through opening 25 when the check valve is unseated from seat 21. The previously described passageway 20 will be seen to pass water entering by way of inlet I I around the sides of member l6 defining air admission passageways 24 and downwardly to be received by certain passageways in lower member l2.

Lower member l2 of the device has an annular or cylindrical external wall 3|] adapted at its upper end to engage a gasket 3| placed on seat 22, and also provided with an annular wall portion 32, spaced concentrically within outer wall or casing 30, which is internally screw-threaded and adapted to be threadedly connected to externally threaded flange ll of upper member ID. The upper end of member 32 engages a gasket 33 seating on a downwardly facing annular seat 34 formed around flange H. Member 32 is connected to external wall 30 by diametrically opposed webs 35, spaced somewhat below the upper ends of members 32 and 30, so to form liquid spaces 36 between said members.

Merging with the lower portion of annular wall 32, between webs 35, is a pair of wall members 40 that extend downwardly between webs 35, each of said wall members 40 integrally joining at its ends with the adjacent ends of webs 35, as indicated at40a, so as to form, with webs 35, barriers below annular wall 32 between the spaces outside and inside said wall 32. The lower portions of these wall members 40 turn inwardly and merge with a substantially horizontal wall 4| having an upwardly projecting annular flange 42 defining a liquid discharge port 43 concentric with casing 36. Formed on the upper end of flange 42 is an upwardly facing annular valve seat 44 for the pre viously mentioned valve 28.

A pair of vertical, horizontally spaced walls 46 join wall 4| at the top and walls 40 and webs 35 at the ends, while spaced below wall 4| and integrally joining and extending between walls 46 is a horizontal wall 41 that extends between and is integrally formed with opposite sides of external casing 30.

The described wall formations provide liquid passages 50 extending downwardly between walls 30 and 32, 4!], leading to a liquid space 5| defined at the bottom by wall member 41. It will be observed that liquid spaces 36 between the upper portions of wall 3|] and annular member 32, defined at the bottom by webs 35, communicate at the ends of said webs with liquid passageways 50. If when the two parts l0 and I2 of the device are screwed together, liquid passageways 2|] in upper member I0 register with passageways 50 in lower member l2, liquid discharged downwardly through passages 20 is received immediately by passageways 50 and flows to liquid space 5|. If, however, in the assembly of the device, liquid spaces 36 should come in part or wholly into register with liquid passages 20, the liquid from passages 20 is simply received by liquid spaces 36 and flows from there to passageways 56 and thence downwardly to liquid space 5|, as before.

Liquid rising from space 5| through port 43 is discharged to liquid spaces or passageways 60 defined by walls 40, webs 35 and wall 3|! on the outside, and by walls 46 on the inside, these passageways leading around the outside of Walls 46 and beneath wall 47 to reach outlet l4, by way of which it is discharged to the discharge line or plumbing fitting coupled thereto.

Normally resting on Valve seat 44 around liquid discharge port 43 is the aforementioned check valve 28, preferably formed of fiber, hard rubber, or composition, such as Bakelite. The upper side of this check valve carries a flexible sealing disc 55, preferably of soft rubber or the like, which is adapted, when check valve 28 is lifted, to seat on the aforementioned downwardly facing valve seat 21 to seal against escape of water by way of passageways 24 and ports 25. As here shown, rubber washer 65 engages in an annular groove 55 formed in check valve 28 as clearly indicated in the drawings. Valve 26 has an upwardly extending stem 68 somewhat loosely received and guided by a valve stem guide bore 69 formed within a cylindrical valve stem guide portion formed integrally with the upper wall |6a of hollow member IS.

The operation of the device is as follows. Assuming, for illustrative purposes, that inlet H is coupled to a usual flush valve, and that outlet i4 is coupled to the line leading to the bowl served by the flush valve, the normal at-rest condition of the device is shown in Fig. 3. It will be noted that the check valve is down, resting on valve seat 44, and that water is present in water collection space or chamber 5! up to the level of the lower surface of valve 28. This water trapped within chamber 5| provides a desirable water seal, filtering any air that may under any circumstances be drawn through port 43 due to suction in the supply line. Assuming now that suction should be developed in the supply line, suflicient to cause the flush valve to open, with the result that the suction extends down to and within chamber 5|. the effect is to cause valve 28 to be pressed more tightly onto its seat 44, exterior air entering by way of passageways 24 and port 25 to maintain atmospheric pressure above the valve to assure tight seating on seat 44. Thus under such circumstances check valve 28 forms a barrier in the flow line, effectively preventing suction in the line ahead of the flush valve from drawing water from the bowl.

In the event that valve 28 does not seat in an air-tight manner on valve seat 64, the protection afforded by the device is not vitiated. In such an instance, while the air suction is not entirely blocked by the valve, this suction is satisfied by drawing air inwardly by way of passageways 24 and port 25, thus breaking the siphon action and preventing the lift of water from the bowl. In some instances it may be desired to construct the device to operate in this manner, and in such an instance the check valve and lower seat 44 are simply so formed as not to seat in air-tight relation.

When the flush valve is discharging through the device, the water from the flush valve enters by way of inlet ll, flows by way of passages 23 1 and 5|] to chamber 5| and acts against the lower side of valve 28, elevating the latter to the position of Fig, 4. The water so flowing from chamber 5| by way of port 43 passes around the sides of walls 46 defining chamber 5|, that is, by way of passages 60, to reach outlet l4, through which it flows into the discharge line below. Pressure of the water flowing upwardly from port 43 holds the upper washer 65 of the check valve tightly against upper seat 21, preventing escape of water at this time by way of air ports 25 and passageways 24.

In some situations the water trap feature may not be necessary, and as a modfication, Fig. 8 shows a form of the invention in which a small liquid discharge port to said liquid outlet, an air bleeder hole 410 is made in wall 41 defining chamber thus permitting the water which would otherwise accumulate within chamber 5| to drain out. In such a form of the device, the

. operation is substantially the same as in the case first described, excepting only thata body of water does not collect in chamber 5|.

The device is reliable and eifective in service,

positively safeguarding against back siphonage. The water trap or seal, which is preferably employed, is a feature of considerable advantage, serving as a barrier between the discharge pipe below and the supply line ahead.

Reference is here made to my copending application, entitled Siphonage preventer for plumbing systems (Case A), filed August 28, 1937, serial No. 161,450, in which are made claims generic to the device disclosed and specifically claimed in the present application.

I have now shown and described one specific illustrative form of the invention; it' will be understood however that various changes in design, structure and arrangement may be made without departing from the spirit and scope of the invention or of the appended claims.

I claim:

1. Ina device of the character described, the combination or a body formed in its top with a liquid inlet, a liquid passageway within said body extending laterally outwardly and downwardly from said inlet, and then formedwith a reverse bend comprising a portion extending back inwardly and then upwardly, in alinement with said inlet, and terminating in an upwardly directed discharge port adapted to discharge a solid column of water, said discharge port being 1 located in vertical alinement with said inlet, an

upwardly facing valve seat around said discharge ort, a liquid outlet opening from the body, a liquid passage within the body leading from said combination of abody formed in its top With a liquid inlet and in its lower portion with a liquid outlet, a liquid passageway within said body extending laterally outwardly and downwardly from said inlet, and then formed with a reverse bend comprising a portion extending back inwardly and then upwardly, in alinement with said inlet, and terminating in an upwardlydirected discharge port adapted to discharged solid column of water, said discharge port, being located in vertical alinement with said inlet, an upwardly lacing valve seat around said discharge port, a liquid passage within the body leading from said liquid discharge port to said liquid outlet, an air inlet passageway in said body terminating in a downwardly discharging port located immediately above said liquid discharge port, a downwardly racing valve seat around said air port, and a check valve mounted for movement between said valveseats to close either the liquid port or the air inlet passage, said check valve being adapted to be moved onto its upper seat by virtue of flow of water upwardly from said liquid port with flushing discharge through the device.

3. In a device of the character described, the combination of a body formed in its top with a liquid inlet, a liquid passage within said body communicating with said liquid inlet, said passage dividing below said inlet into two branches which extend outwardly in opposite directions, then downwardly, then back toward one another and join at a point below said liquid inlet, an upwardly discharging liquid port located within the body below said-inlet, said port leading from the lower juncture of said liquid passage branches, a liquid passage within the body leading from the discharge side of said liquid port around said lower juncture and then downwardly to said liquid outlet, an air passage in the body leading inwardlyfrom the exterior of the body between said branches and terminating in a downwardly discharging port located above and in communication with said liquid discharge port, and a check valve mounted for movement between said liquid and air ports, so as to close either the liquid port or the air inlet port, said check valve being adapted to be moved onto its upper seat by virtue of how of water upwardly from said liquid port with flushing discharge through the device.

4. In a device of the character described, the combination of a body formed in its top with a liquid inlet, a liquid passage within said body communicating with said liquid inlet, said passage dividing below said inletinto two branches which extend outwardly in opposite directions, then downwardly, then back toward one another and join at a point below said liquid inlet, an

upwardly" discharging liquid port located within the body below said inlet, said port leading from the lower juncture of said liquid passage branches, a liquid passage within the body leading from the discharge; side of said liquid port and comprising two branches leading around said lower juncture and then downwardly to said liquid outlet, an air passage in the body leading inwardly from the exterior of the body between said first mentioned branches and terminating in a downwardly discharging port located above and in communication with said liquid discharge port, and a check valve mounted for movement between said liquid and air ports, so as to close either the liquid port or the air inlet port, said check valve being adaptedto be moved onto its upper set by virtue of flow of water upwardly from said liquid port with flushing discharge through the device.

5. In a device of the character described, the combination of detachably connected upper and lower casing members forming a closed body, a centrally located liquid inlet in the top of the upper casing member, a liquid outlet in the lower portion of the lower casing member, an air admission passageway opening externally of the upper casing member and leading to a downwardly directed air port located below said inlet, a downwardly facing valve seat on the bottom of said member around said air port, a liquid passage within the upper member leading laterally and downwardly from said inletand discharging downwardly at a point laterally offset from the vertical axis defined by said centrally located liquid inlet, a liquid passage in the lower casing member opening upwardly in a position to receive liquid from the liquid passage in the upper member when the upper and lower casing members are connected, said last mentioned liquid passage extending downwardly, centrally and upwardly to terminate in an upwardly directed liquid discharge port located below said air port and in alinement with said liquid inlet, an upwardly facing valve seat on the lower member around said liquid port and opposed to the valve seat around the air port, a liquid passage within the lower casing member leading from the discharge side of said liquid port to said liquid outlet, and a check valve member movable between said liquid and air port seats to close either the liquid port or the air inlet passage, said check valve being adapted to be moved onto its upper seat by virtue of flow of water upwardly from said liquid port with flushing discharge through the device.

6. In a device of the character described, the combination of screwthreadedly connected upper and lower casing members forming a closed body, a centrally located liquid inlet in the top of the upper casing member, a liquid outlet in the lower portion of the lower casing member, an air admission passageway opening externally of the upper casing member and leading to a downwardly directed air port located below said inlet, a downwardly facing valve seat on the bottom of said member around said air port, a liquid passage within the upper member leading laterally and downwardly from said inlet and discharging downwardly at 'a point laterally ofiset from the vertical axis defined by said centrally located liquid inlet, a liquid passage in the lower casing member opening upwardly in a position to receive liquid from the liquid passage in the upper member when the upper and lower casing members are connected, said last mentioned liquid passage extending downwardly, centrally and upwardly to terminate in an upwardly directed liquid discharge port located below said air port and in alinement with said liquid inlet, an upwardly facing valve seat on the lower member around said liquid port and opposed to the valve seat around the air port, a liquid passage within the lower-casing member leading from the discharge side of said liquid port to said liquid outlet, and a check valve member movable between said liquid and air port seats to close either the liquid port or the air inlet passage, said check valve being adapted to be moved onto its upper seat by virtue of flow of water upwardly from said liquid port with flushing discharge through the device.

7. In a device of the character described, the combination of screwthreadedly connected upper and lower casing members forming a body, a liquid inlet in the top of the upper casing member, a liquid outlet in the lower portion of the lower casing member, walls within and formed integrally with the upper casing member defining an air admission passageway extending inwardly into the upper casing member and leading to a downwardly opening air port located below and in alinement with said liquid inlet, there being a passage for liquid fiow from said inlet leading around said air passageway walls and opening downwardly outside said air port, walls within and formed integrally with the lower casing member defining a liquid passageway in said lower casing member opening upwardly in a position to receive liquid from the passageway in the upper casing member, said liquid passageway in the lower casing member extending downwardly, then centrally of the lower casing member, and

finally terminating in an upwardly opening liquid port located below and in opposition to said air port, there being a passageway for liquid fiow within the lower casing member from the discharge side of said liquid port downwardly past said liquid passageway defining walls to said liquid outlet, and a check valve member movable between said liquid port and air port to close either the liquid port or the air inlet passage, said check valve being adapted to be moved onto its upper seat by virtue of fiow of water upwardly from said liquid port with flushing discharge through the device.

8. In a device of the character described, the combination of screwthreadedly connected upper and lower casing members forming a body, a liquid inlet in the top of the upper casing member, a liquid outlet in the lower portion of the lower casing member, walls within and formed integrally with the upper casing member defining an air admission passageway extending inwardly into the upper casing member and leading to a downwardly opening air port located below and in alinement with said liquid inlet, there being a passage for liquid fiow from said inlet leading around said air passageway walls. and opening downwardly outside said liquid port, walls within and formed integrally with the lower casing member defining a liquid passageway in said lower casing member opening upwardly in a position to receive liquid from the passageway in the upper casing member, engageable gasketed seats on the upper and lower casing members defining the lower opening of the liquid passage in the upper casing member and the upper opening of the cooperating liquid passage in the lower casing member, said liquid passageway in the lower casing member extending downwardly, then centrally of the lower casing member, and finally terminating in an upwardly opening liquid port located below and in opposition to said air port, there being a passageway for liquid fiow within the lower casing member from the discharge side of said liquid port downwardly past said liquid passageway defining walls to said liquid outlet, and a check valve member movable between said liquid port and air port to close either the liquid port or the air inlet passage, said check valve being adapted to be moved onto its upper seat by virtue of flow of water upwardly from said liquid port with flushing discharge through the device.

9. In a device of the character described, the combination of a body formed in its top with a liquid inlet and in its lower portion with a liquid outlet, an upwardly discharging liquid port within said body vertically alined with said liquid inlet, said port being adapted to discharge a solid column of water, a chamber within the body receiving liquid from said discharge port, said chamber being in communication with said liquid outlet, an air admission passageway in said body terminating in a downwardly directed air port opening to said chamber immediately above said liquid discharge port, a check valve mounted for movement between said liquid and air ports, so as to close either the liquid port or the air inlet port, said checkvalve being adapted to be moved onto its upper seat by virtue of discharge of a solid column of water upwardly from said liquid port, and a liquid passage within the body leading horizontally from said liquid inlet to a point beyond the outer limits of said air and liquid ports and thence downwardly to the side of said ports, finally leading inwardly and upwardly to said liquid discharge port.

10. In a device of the character described, the combination of a body formed in its top with a liquid inlet and in its lower portion with a liquid outlet, a liquid passage within said body communicating with said liquid inlet, said passage dividing below said inlet into two branches which extend outwardly, then downwardly, then back toward body leading inwardly from the exterior of the body between said branches and terminating in a downwardly discharging port located above and in communication with said liquid discharge port,

and a check valve mounted for movement between said liquid and air ports, so as to close either the liquid port or the air inlet port, said check valve being adapted to be moved onto its upper seat by virtue of flow of water upwardly from said liquid port with flushing discharge through the device.

ROBERT R. FOX. 

